Abstract:
As feed costs continue to rise, new technologies that will improve feed efficiency in a safe and
consistent manner will become more critical for beef cattle production. With this in mind, two
experiments were conducted. Experiment 1, a randomized complete block design study utilizing 144
Bonsmara-type steers (233 ± 0.8 kg BW) was conducted to examine the effect of a liquid
Lactobacillus fermentation prototype (LFP; Diamond V, Cedar Rapids, IA) on performance of feedlot
cattle. The 134 day study was conducted on a commercial beef research facility in South Africa. Upon
arrival, cattle were processed and allocated to a free-range pasture for 8 d. On d 9, cattle were further
processed and then blocked by arrival body weight and randomly assigned to one of 3 treatments with
8 pens per treatment and 6 steers per pen. Dietary treatments included a control diet that contained 0,
5, or 10 g LFP per head daily. Treatments were provided a in starter (d 9 to 29), grower (d 30 to 43)
and finisher diet (d 44 to 134). The cattle were then slaughtered and carcasses data obtained.
Experiment 2, a 3x3 Latin Square design conducted with three Beefmaster steers (700kg ±20kg) fitted
with ruminal cannulae to establish a possible mode of action of the LFP supplement. Rumen
fermentation parameters namely VFA concentration, rumen NH3-N, ruminal pH, lactic acid
concentration and NDF disappearance were measured. In experiment 1 no differences were detected
(P > 0.05) among treatments for BW gain, ADG, DMI or any of the carcass traits that were measured.
Overall, (d 9 to 134), FCR was improved (P = 0.03) for 5 g LFP supplemented steers compared with
those receiving 0 or 10 g LFP (4.70 vs. 4.82, 4.86). No differences in FCR, however, were reported,
between treatment groups, in each individual feeding phase. Results from experiment 1 suggest that
LFP does improve feed efficiency of beef cattle fed a typical South African feedlot diet and that the
effect was dose dependent. Results from experiment 2 showed no differences in any of the rumen
fermentation parameters that we measured. Further research on the mode of action of LFP is
warranted.
